I guess we need to keep our offline computers enclosed within a copper wire mesh.
Make sure the whole room is a Faraday cage.
I think sound proofing and no windows(physical ones that is) is also in order...
If you're too paranoid to have a window in the room you use your computer in, you're
way too paranoid to have MS Windows on your computer. Hell, you're probably too paranoid for Linux. OpenBSD with disk, swap, and RAM encryption, all networking disabled at compile time, no sudo, root password set to randomness.